The present invention relates to a suture manipulating and/or cutting implement, and particularly to a surgical implement for manipulating a knotted suture to properly locate the knot thereof with respect to tissue being sutured, and then for removing excess suture from the knot.
Surgical procedures are increasingly being performed through small portals, or incisions leading directly to the surgical site operated on, thereby minimizing damage to the adjacent tissue. The technique is also known by the name endoscopy. Since the area operated on is not directly visible to the surgeon, the surgeon generally relies on a system of internal illumination and imaging through a small video camera and is guided by an enlarged image generated on a monitor screen.
All necessary operations must therefore be performed through a narrow opening. The size of such an opening limits the size of the instruments used and the free space available to manipulate them. Small-size cutting, grasping, debriding and piercing instruments, capable of operating through small portals, have been developed for this purpose.
Suturing is also possible, and many suture passing and stitching devices are available to the endoscopist. Tying a knot endoscopically remains, however, barely possible. The alternative solution is to use an excess length of suture and to bring the end of the strands to the outside for easy tying. One of several types of sliding knots, similar to the “hangman's knot”, is formed at the outside, then moved down the remaining strand through the access portal, and tightened firmly over the tissue stitched. The excess length of suture is then cut off at a small distance above the knot. The length of the suture end remaining after cutting is important: if it is too long, it may cause irritation; if it is too short, the knot may fail to hold.
The steps described above are generally performed by first using a knot manipulator device for pushing the suture, and then a cutting device, such as an endoscopic suture scissors, for cutting off the excess. This is disadvantageous because no “built in” relationship exists between the knot placement and the cutting location. Moreover, introducing a second instrument into the portal leaves little or no room for manipulating it to the desired position.
On the other hand, withdrawing the knot manipulator in order to make room for the cutter makes it difficult and time-consuming to locate the cutter at the right position.
Published U.S. patent application Ser. No. 2002/0123758 A1, published Sep. 5, 2002, by Bachman et al, discloses a surgical knot pushing and cutting device including a pushing interface for pushing a knotted suture to a desired location, and a cutting member for removing excess suture. However, the device described is relatively large in size, and therefore requires relatively large portals or incisions. Moreover, the described device is of relatively complicated construction, and therefore is relatively expensive to produce and complicated to operate.